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51.
We obtain size estimates for the distribution function of the bilinear Hilbert transform acting on a pair of characteristic
functions of sets of finite measure, that yield exponential decay at infinity and blowup near zero to the power −2/3 (modulo
some logarithmic factors). These results yield all known Lp bounds for the bilinear Hilbert transform and provide new restricted weak type endpoint estimates on Lp1 × Lp2 when either 1/p1 + 1/p2 = 3/2 or one of p1, p2 is equal to 1. As a consequence of this work we also obtain that the square root of the bilinear Hilbert transform of two
characteristic functions is exponentially integrable over any compact set. 相似文献
52.
Mousavi SH Khanikaev AB Neuner B Avitzour Y Korobkin D Ferro G Shvets G 《Physical review letters》2010,105(17):176803
Highly confined "spoof" surface plasmons (SSPs) are theoretically predicted to exist in a perforated metal film coated with a thin dielectric layer. Strong modes confinement results from the additional waveguiding by the layer. Spectral characteristics, field distribution, and lifetime of these SSPs are tunable by the holes' size and shape. SSPs exist both above and below the light line, offering two classes of applications: "perfect" far-field absorption and efficient emission into guided modes. It is experimentally shown that these plasmonlike modes can turn thin, weakly absorbing semiconductor films into perfect absorbers. 相似文献
53.
Slobodyanyuk Evgeniy Yu. Volochnyuk Dmitriy M. 《Chemistry of Heterocyclic Compounds》2019,55(3):202-204
Chemistry of Heterocyclic Compounds - Microreview describes recent advances in the synthesis of alkyl-substituted 1,3-oxazoles via CH activation reaction. The latest selected examples... 相似文献
54.
Osipov Dmitriy V. Artyomenko Alina A. Osyanin Vitaly A. Klimochkin Yuri N. 《Chemistry of Heterocyclic Compounds》2019,55(3):261-265
Chemistry of Heterocyclic Compounds - Reactions of 4Н-chromene-3-carbaldehydes and 1Н-benzo[f]chromene-3-carbaldehydes with 4-aminocoumarin were used to obtain a series of... 相似文献
55.
I. Fita D. Mogilyansky V. Markovich R. Puzniak A. Wisniewski L. Titelman L. Vradman M. Herskowitz V.N. Varyukhin G. Gorodetsky 《Journal of Non》2008,354(47-51):5204-5206
Magnetic and structural properties of nanocrystalline LaCoO3 with particle size ranging from 25 to 38 nm, prepared by the citrate method, were investigated. All nanoparticles exhibit ferromagnetism below TC ≈ 85 K. It was found that the unit-cell volume increases monotonically with decreasing particle size and ferromagnetic (FM) moment increases simultaneously with lattice expansion, whereas TC remains nearly unchanged. It appears that both magnetic and structural properties of LaCoO3 nanoparticles are size-dependent due to the surface effect. On the other hand, an applied pressure suppresses strongly the FM phase leading to its disappearance at ~11 kbar. Remarkably, the TC does not change visibly under pressure. Our data reveal that the ferromagnetism in LaCoO3 nanoparticles, likely related to the intermediate-spin (IS) Co3+ state, is simply controlled by the unit-cell volume. Within this scenario, the FM coupled IS states appear/disappear with expanding/compressing the lattice and/or Co–O bonds. 相似文献
56.
Torsional states caused by vibrations of hydroxyl groups in the methanediol molecule and its two deuterated analogues – DO(CH2)OH and DO(CH2)OD were analysed at MP2/cc-pVTZ and CCSD(T)/cc-pVQZ levels of theory. In the first case, 2D PES and 2D surfaces of kinematic coefficients were calculated with geometry optimisation for all other geometric parameters, and in the second case, only the energy of optimised configurations at the MP2/cc-pVTZ level of theory was determined. Then 2D PES was recounted to the complete basis set (CBS) limit by extrapolating the results of calculations at the MP2/cc-pVTZ and MP2/cc-pVQZ levels of theory The calculated values were then averaged over four equivalent points on the coordinate plane. Hamiltonian matrices were constructed using DVR and Fourier methods. After their subsequent diagonalization, the energies of the stationary torsional states were computed. Their classification by C2V(M) and CS(M) molecular symmetry groups has been performed. The splitting values due to the tunnelling of the thirty most deeply located torsional states in the three studied molecules were also determined. The torsional states, internal rotation barriers, and tunnelling frequencies in the molecules of methanediol and hydrogen trioxide were compared. 相似文献
57.
Set-Valued and Variational Analysis - Subgradient and Newton algorithms for nonsmooth optimization require generalized derivatives to satisfy subtle approximation properties: conservativity for the... 相似文献
58.
Mawlood Mohammad N. Potapov Andrei Yu. Vandyshev Dmitriy Yu. Shikhaliev Khidmet S. Potapov Mikhail А. Ledenyova Irina V. Kosheleva Evgeniya А. 《Chemistry of Heterocyclic Compounds》2019,55(11):1075-1079
Chemistry of Heterocyclic Compounds - Condensation of 1H-1,2,4-triazolo-5-diazonium salts with 1,3-cyclohexanedione, accompanied by cascade processes of cyclization and oxidative aromatization,... 相似文献
59.
Gimranov Dmitriy R. Abdullina Aisylu F. Sevast’yanova Ekaterina V. Petrova Yuliya Yu. 《平面色谱法杂志一现代薄层色谱法》2015,28(5):343-351
JPC – Journal of Planar Chromatography – Modern TLC - The thin-layer chromatography (TLC) procedures of metal cations, modified with amines and cationic surfactant micelles, followed by... 相似文献
60.