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131.
Michael Krivelevich Benny Sudakov Van H. Vu Nicholas C. Wormald 《Random Structures and Algorithms》2001,18(4):346-363
Random d‐regular graphs have been well studied when d is fixed and the number of vertices goes to infinity. We obtain results on many of the properties of a random d‐regular graph when d=d(n) grows more quickly than . These properties include connectivity, hamiltonicity, independent set size, chromatic number, choice number, and the size of the second eigenvalue, among others. ©2001 John Wiley & Sons, Inc. Random Struct. Alg., 18: 346–363, 2001. 相似文献
132.
A method for investigation of the behavior of the distribution of the maximum of two Gaussian families during an orthogonalization
process is described. Bibliography: 1 title.
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 244, 1997, pp. 285–294.
Translated by A. Sudakov. 相似文献
133.
V. N. Sudakov 《Journal of Mathematical Sciences》2000,99(2):1197-1200
The main result: If the dimension of a Euclidean space with measure is high enough, only the first observation from a long
series of observations with random independent choice of projection gives essential information on the measure. Bibliography:
8 titles.
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 244, 1997, pp. 295–301.
Translated by V. Sudakov. 相似文献
134.
135.
136.
The compressibility effect on the cylinder drag reduction due to air suction through the surface of a central body in a circular vortex cell is estimated on the basis of the solution of the steady Reynolds equations closed by the shear stress transfer model, together with the continuity, energy, and state equations. 相似文献
137.
Robert N. Boute Stephen M. Disney Marc R. Lambrecht Benny Van Houdt 《European Journal of Operational Research》2014
We consider a supply chain in which orders and lead times are linked endogenously, as opposed to assuming lead times are exogenous. This assumption is relevant when a retailer’s orders are produced by a supplier with finite capacity and replenished when the order is completed. The retailer faces demands that are correlated over time – either positively or negatively – which may, for example, be induced by a pricing or promotion policy. The auto-correlation in demand affects the order stream placed by the retailer onto the supplier, and this in turn influences the resulting lead times seen by the retailer. Since these lead times also determine the retailer’s orders and its safety stocks (which the retailer must set to cover lead time demand), there is a mutual dependency between orders and lead times. The inclusion of endogenous lead times and autocorrelated demand represents a better fit with real-life situations. However, it poses some additional methodological issues, compared to assuming exogenous lead times or stationary demand processes that are independent over time. By means of a Markov chain analysis and matrix analytic methods, we develop a procedure to determine the distribution of lead times and inventories, that takes into account the correlation between orders and lead times. Our analysis shows that negative autocorrelation in demand, although more erratic, improves both lead time and inventory performance relative to IID demand. Positive correlation makes matters worse than IID demand. Due to the endogeneity of lead times, these effects are much more pronounced and substantial error may be incurred if this endogeneity is ignored. 相似文献
138.
Marc Comet Vincent Pichot Benny Siegert Eric Fousson Julien Mory Florence Moitrier Denis Spitzer 《Journal of nanoparticle research》2011,13(5):1961-1969
This article reports on the preparation of chromium(III) oxide nanoparticles by detonation. For this purpose, a high explosive—hexahydro-1,3,5-trinitro-1,3,5-triazine
(RDX)—has been solidified from a solution infiltrated into the macro- and mesoporosity of Cr2O3 powder obtained by the combustion of ammonium dichromate. The resulting Cr2O3/RDX nanocomposite material was embedded in a cylindrical charge of pure explosive and detonated in order to fragment the
metallic oxide into nanoparticles. The resulting soot contains Cr2O3 nanoparticles, nanodiamonds, amorphous carbon species and inorganic particles resulting from the erosion by the blast of
the detonation tank wall. The purification process consists in (i) removing the carbonaceous species by an oxidative treatment
at 500 °C and (ii) dissolving the mineral particles by a chemical treatment with hydrofluoric acid. Contrary to what could
be expected, the Cr2O3 particles formed during the detonation are twice larger than those of initial Cr2O3. The detonation causes the fragmentation of the porous oxide and the melting of resulting particles. Nanometric droplets
of molten Cr2O3 are ejected and quenched by the water in which the charge is fired. Despite their larger size, the Cr2O3 nanoparticles prepared by detonation were found to be less aggregated than those of the initial oxide used as precursor.
Finally, the Cr2O3 synthesized by detonation was used to prepare a superthermite with aluminium nanoparticles. This material possesses a lower
sensitivity and a more regular combustion compared to the one made of initial Cr2O3. 相似文献
139.
Proton transfer and dissociation processes following excitation of the OH or NH stretching modes of the proton-bound complex GlyLysH(+) are studied by classical trajectories. "On the fly" simulations with the PM3 semiempirical electronic structure method for the potential surface are used. Initial conditions are sampled to correspond to the v=1 excited state of the OH or NH stretching modes. Five different conformers of the complex are studied as initial structures. The main findings are (1) Photoinduced proton transfer is on the picosecond time scale. (2) Proton transfer is much faster than the processes of dissociation. (3) Proton transfer involves different sites. Most trajectories show sequences of two proton transfer events. (4) The proton transfer events show high selectivity with regard to the initially excited vibration and the initial structure. (5) Photodissociation of the complex occurs on a typical time scale of 100 ps. (6) Conformational transitions are found to be often faster than proton transfer. These results have implications for the mass spectrometry of complexes, for dynamics of proton wires, and for proton migration in proteins. 相似文献
140.
Benny Febriansyah Tetiana Borzda Daniele Cortecchia Stefanie Neutzner Giulia Folpini Teck Ming Koh Yongxin Li Nripan Mathews Annamaria Petrozza Jason England 《Angewandte Chemie (International ed. in English)》2020,59(27):10791-10796
Published studies of layered (2D) (100)‐oriented hybrid lead‐bromide perovskites evidence a correlation between increased inter‐octahedral (Pb‐Br‐Pb) distortions and the appearance of broadband white light emission. However, the impact of distortions within their constituent [PbBr6]4? octahedra has yet to be assessed. Herein, we report two new (100)‐oriented 2D Pb‐Br perovskites, whose structures display unusually high intra‐octahedral distortions, whilst retaining minimal inter‐octahedral distortions. Using a combination of temperature‐dependent, power‐dependent and time‐resolved photoluminescence spectroscopic measurements, we show that increased intra‐octahedral distortion induces exciton localization processes and leads to formation of multiple photoinduced emissive colour centres. Ultimately, this leads to highly Stokes‐shifted, ultrabroad white light emission at room temperature. 相似文献