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31.
Péter Csóka P. Jean-Jacques Herings László Á. Kóczy 《Mathematical Methods of Operations Research》2011,74(1):41-52
We provide two new characterizations of exact games. First, a game is exact if and only if it is exactly balanced; and second,
a game is exact if and only if it is totally balanced and overbalanced. The condition of exact balancedness is identical to
the one of balancedness, except that one of the balancing weights may be negative, while for overbalancedness one of the balancing
weights is required to be non-positive and no weight is put on the grand coalition. Exact balancedness and overbalancedness
are both easy to formulate conditions with a natural game-theoretic interpretation and are shown to be useful in applications.
Using exact balancedness we show that exact games are convex for the grand coalition and we provide an alternative proof that
the classes of convex and totally exact games coincide. We provide an example of a game that is totally balanced and convex
for the grand coalition, but not exact. Finally we relate classes of balanced, totally balanced, convex for the grand coalition,
exact, totally exact, and convex games to one another. 相似文献
32.
The radiation emitted by a heated body is generally quoted as a typical example of incoherent radiation, in distinction to laser radiation. One is nearly isotropic, the other highly directional; one is spectrally broad, the other quasi-monochromatic. It may come as a surprise that the thermal radiation of a large number of substances is coherent, both in space and time, when it is observed at a distance from the body that is shorter than the wavelength. This behaviour can be understood within an electromagnetic approach to thermal emission. Several recent experiments have confirmed these unexpected properties. 相似文献
33.
34.
Michel Dedieu Yves-Louis Pascal Pierre Dizabo Jean-Jacques Basselier 《Journal of mass spectrometry : JMS》1977,12(3):153-158
The mass spectra of the title compounds always show an intense molecular ion. Some fissions involve loss of the ethylenic group, while others are related to cleavage of the dithiane ring, eventually followed by recyclizations involving the ethylenic chain stabilized by the resonance possibilities. If a phenyl group is present in the ethylenic chain, the spectra are modified by the formation of the very stable benzothiopyrylium ion. 相似文献
35.
Jean-Jacques Vasseur Bernard Rayner Jean-Louis Imbach 《Journal of heterocyclic chemistry》1988,25(2):389-392
We have elucidated the exact mechanism of apurinic oligodeoxynucleotide d(Tp[AP]pT) cleavage by phenylhydrazine and shown that the final isolated product is in fact a 3-substituted derivative of 1-phenyl-pyrazole. 相似文献
36.
Odile Convert Catherine Deville Jean-Jacques Godfroid 《Magnetic resonance in chemistry : MRC》1977,10(1):220-223
The 13C n.m.r. spectrum of the bridge substituted dicoumarols are interpreted in order to obtain structural information for quantitative structure-activity relationships. The results are in agreement with those obtained by 1H n.m.r. These dicoumarols exhibit double restricted rotation around both bridge bonds. 相似文献
37.
Françoise Fournier Suzanne Altenburger-Combrisson Nguyen Kim Cuong Jean-Jacques Basselier 《Tetrahedron》1979,35(22):2633-2637
The addition of tetracyanotehylene to 2H-pyrans 1 results in a mixture of two isomeric adducts 6. The thermal decomposition of the compounds 6 gives rise to both a small percentage of the retro Diels-Alder, and a new mode of evolution leading to a mixture of furans (E+Z) 7. A detailed interpretation of the 13C spectra of the compounds 7 was established by comparison with the 13C spectra of 2,5-diphenylfuran and trans-stilbene. The structure 7 is confirmed by chemical degradation. 相似文献
38.
39.
M'Hamed Ali Hamza Guy Serratrice Jean-Jacques Delpuech 《Magnetic resonance in chemistry : MRC》1981,16(2):98-102
Carbon-13 chemical shifts, spin-lattice relaxation times and nuclear Overhauser enhancement factors are reported for five polyfluoroaromatic compounds at 28°C. In all cases the relaxation of the fluorine bearing carbon is predominantly dipolar. Effective correlation times are smaller than those of the analogous benzene derivatives by a factor of 3–4, in qualitative agreement with predictions from the Stokes–Einstein diffusion theory. The T1 values for the para-carbon of monosubstituted fluorobenzenes is clearly shorter than the T1 values for the ortho- and meta-carbons. This phenomenon was traced to anisotropic tumbling, and D∥ and D⊥ diffusion coefficients were computed using Woessner's equations for molecules assumed to behave like symmetric rotors about their C2 in-plane principal symmetry axis. Equal tumbling ratios, D∥/D⊥, were found in this way for toluene and perfluorotoluene. 相似文献
40.
Cheikh?L? Jean-Jacques?Aaron Václav?Kozmík Ji?í?Svoboda Jean-Claude?Brochon Li?Na 《Journal of fluorescence》2010,20(5):1037-1047
The synthesis, electrochemical and optical properties of three fluorescent substituted thieno[3,2-b][1]benzothiophenes (TBT)
derivatives, including 3-methoxythieno[3,2-b][1]benzothiophene (3-MeO-TBT), 2,3-dimethylthieno[3,2-b][1]benzothiophene (2,3-diMe-TBT),
and 6-methoxythieno[3,2-b][1]benzothiophene-2-carboxylate (6-MeO-TBT-2-COOMe), were investigated. The oxidation potential
values varied between 1.40 and 1.20 V/SCE according to the electronic substituent effect, and electropolymerization attempts,
performed in 0.1 M LiClO4 acetonitrile solution, led to the formation of very thin films of poly(3-MeO-TBT) and poly(2,3-di-Me-TBT). Electronic absorption
spectra, fluorescence excitation and emission spectra, fluorescence quantum yields (ΦF) , lifetimes (τF), and other photophysical parameters of the three new TBT derivatives were measured in DMSO solutions at room temperature.
For the methyl-and methoxy-substituted TBT derivatives, the fluorescence emission peak were slightly red shifted relative
to that of unsubstituted TBT (Δλem = 1–12 nm) whereas, in the case of 6-MeO-TBT-2-COOMe, a rather strong red-shift (Δλem = 73 nm) was attributed to the existence of a “push-pull” electronic interaction of the MeO and COOMe groups. All ΦF values were rather high, varying between 0.11 and 0.35, according to the substituent effect. Fluorescence decays were mono-exponential
and τF values were very short, ranging between 0.11 and 0.30 ns for the substituted TBT derivatives until study. 相似文献