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排序方式: 共有109条查询结果,搜索用时 17 毫秒
91.
92.
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
93.
Access to a series of truncated ATP analogs, as potential anti-tuberculosis agents, has been explored via alkylation and acylation of 3-aminophenol, whereas chloroacetylation, using chloroacetyl chloride, and subsequent Arbuzov phosphonation of a series of 3-substituted anilines have afforded a series of phosphonate derivatives as potential antimalarial agents. 相似文献
94.
Santiago DN Pevzner Y Durand AA Tran M Scheerer RR Daniel K Sung SS Lee Woodcock H Guida WC Brooks WH 《Journal of chemical information and modeling》2012,52(8):2192-2203
Computational methods involving virtual screening could potentially be employed to discover new biomolecular targets for an individual molecule of interest (MOI). However, existing scoring functions may not accurately differentiate proteins to which the MOI binds from a larger set of macromolecules in a protein structural database. An MOI will most likely have varying degrees of predicted binding affinities to many protein targets. However, correctly interpreting a docking score as a hit for the MOI docked to any individual protein can be problematic. In our method, which we term "Virtual Target Screening (VTS)", a set of small drug-like molecules are docked against each structure in the protein library to produce benchmark statistics. This calibration provides a reference for each protein so that hits can be identified for an MOI. VTS can then be used as tool for: drug repositioning (repurposing), specificity and toxicity testing, identifying potential metabolites, probing protein structures for allosteric sites, and testing focused libraries (collection of MOIs with similar chemotypes) for selectivity. To validate our VTS method, twenty kinase inhibitors were docked to a collection of calibrated protein structures. Here, we report our results where VTS predicted protein kinases as hits in preference to other proteins in our database. Concurrently, a graphical interface for VTS was developed. 相似文献
95.
Archive for Rational Mechanics and Analysis - 相似文献
96.
M.J. Corden J.D. Dowell J. Garvey R.J. Homer M. Jobes I.R. Kenyon T. McMahon R.C. Owen K.C.T.O. Sumorok R.J. Vallance P.M. Watkins J.A. Wilson P. Sonderegger B. Chaurand A. Romana R. Salmeron 《Physics letters. [Part B]》1981,98(3):220-224
J/ψ production at 40 GeV/c by π±, K±, p and incident on hydrogen has been studied and results compared with those obtained on tungsten in the same experiment. On hydrogen, J/ψ cross-section ratios relative to π? have been measured to be (for . The suppression of the proton induced cross sections shows the importance of calence quark-antiquark fusiin J/ψ production at this energy (i.e. MJ2/ψ/s=0.13). 相似文献
97.
Michelle M. Meighan Michael W. Keebaugh Alicia M. Quihuis Stacy M. Kenyon Mark A. Hayes 《Electrophoresis》2009,30(21):3786-3792
A novel method capable of differentiating and concentrating small molecules in bulk solution termed “electrophoretic exclusion” is described and experimentally investigated. In this technique, the hydrodynamic flow of the system is countered by the electrophoretic velocity to prevent a species from entering into the channel. The separation can be controlled by changing the flow rate or applied electric field in order to exclude certain species selectively while allowing others to pass through the capillary. Proof of principle studies employed a flow injection regime of the method and examined the exclusion of Methyl Violet dye in the presence of a neutral species. Methyl Violet was concentrated almost 40 times the background concentration in 30 s using 6 kV. Additionally, a threshold voltage necessary for exclusion was determined. The establishment of a threshold voltage enabled the differentiation of two similar cationic species: Methyl Green and Neutral Red. 相似文献
98.
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
99.
100.