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81.
The concept of individuality in quantum mechanics shows radical differences from the concept of individuality in classical
physics, as E. Schr?dinger pointed out in the early steps of the theory. Regarding this fact, some authors suggested that
quantum mechanics does not possess its own language, and therefore, quantum indistinguishability is not incorporated in the
theory from the beginning. Nevertheless, it is possible to represent the idea of quantum indistinguishability with a first-order
language using quasiset theory (Q). In this work, we show that Q cannot capture one of the most important features of quantum
non-individuality, which is the fact that there are quantum systems for which particle number is not well defined. An axiomatic
variant of Q, in which quasicardinal is not a primitive concept (for a kind of quasisets called finite quasisets), is also
given. This result encourages the searching of theories in which the quasicardinal, being a secondary concept, stands undefined
for some quasisets, besides showing explicitly that in a set theory about collections of truly indistinguishable entities,
the quasicardinal needs not necessarily be a primitive concept.
Graciela Domenech — Fellow of the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). 相似文献
82.
Robert M Caudle Andrew J Mannes Jason Keller Federico M Perez Shelby K Suckow John K Neubert 《BMC neuroscience》2007,8(1):30
Background
Several investigators have coupled toxins to neuropeptides for the purpose of lesioning specific neurons in the central nervous system. By producing deficits in function these toxin conjugates have yielded valuable information about the role of these cells. In an effort to specifically stimulate cells rather than kill them we have conjugated the neuropeptide substance P to the catalytic subunit of cholera toxin (SP-CTA). This conjugate should be taken up selectively by neurokinin receptor expressing neurons resulting in enhanced adenylate cyclase activity and neuronal firing. 相似文献83.
Bella Dolgin Valery Bulatov Israel Schechter 《Analytical and bioanalytical chemistry》2009,395(7):2151-2159
A nondestructive method for quantitative parchment characterization and sensitive indication of its deterioration stage was
developed. Synchronous fluorescence (SF) measurements were applied for the first time to parchment samples. The method provides
detailed spectral features, which are useful for parchment characterization. The discrimination of parchment samples into
groups (modern, historical, and artificially aged) was successfully performed. The SF spectra could be resolved into specific
fluorophores, which were related to the parchment condition. The spectral data indicate a continuous change in the collagen-to-gelatin
ratio during the aging process. Depth-resolved synchronous fluorescence spectra were also measured. The data indicate that
parchments possess a layered structure, and the dominant fluorophore in the upper layer is different from those in the lower
layers. Layer-resolved profiling allows for quantifying the contribution of each fluorophore in each given layer. This way,
significant differences between modern, artificially aged, and historical samples can be observed. 相似文献
84.
Bravo-Castillero Julian; Rodriguez-Ramos Reinaldo; Mechkour Houari; Otero Jose A.; Sabina Federico J. 《The Quarterly Journal of Mechanics and Applied Mathematics》2008,61(3):311-332
In this work, based on the periodic unfolding homogenizationtechnique, the limiting equations modelling the behaviour ofthree-dimensional magneto-electro-elastic periodic structuresare rigorously established. The local problems and the correspondinghomogenized coefficients of the elastic, dielectric, magneticpermittivity, piezoelectric, piezomagnetic and magneto-electric(ME) tensors are explicitly described. The homogenization modelis exemplified for laminated composites and a unified generalformula for all effective properties of periodic multilaminatedmagneto-electro-elastic composites is obtained. This formulais applied to investigate the global behaviour for the importantcase of transversely isotropic constituents and any finite numberof layers in each periodic cell. Examples that provide theoreticalevidence of the presence of both a product property and theME effect are given. 相似文献
85.
86.
Federico Gallizio Angelo Iollo Bartosz Protas Luca Zannetti 《Physica D: Nonlinear Phenomena》2010,239(3-4):190-201
This investigation concerns solutions of the steady-state Euler equations in two dimensions featuring finite area regions with constant vorticity embedded in a potential flow. Using elementary methods of the functional analysis we derive precise conditions under which such solutions can be uniquely continued with respect to their parameters, valid also in the presence of the Kutta condition concerning a fixed separation point. Our approach is based on the Implicit Function Theorem and perturbation equations derived using shape-differentiation methods. These theoretical results are illustrated with careful numerical computations carried out using the Steklov–Poincaré method which show the existence of a global manifold of solutions connecting the point vortex and the Prandtl–Batchelor solution, each of which satisfies the Kutta condition. 相似文献
87.
Federico Laudisa 《Foundations of Physics》2000,30(9):1525-1538
It is usually held that the standard collapse model of a quantum measurement process grounds a kind of fundamental time asymmetry. The question whether and how it should be possible to reconstruct uniquely one's own history in an Everett no-collapse interpretation of quantum theory is investigated. A particular approach to the Everett interpretation, due to John S. Bell, is considered, according to which one of the chief claims of the Everett quantum theory is precisely that it allows us to do without the notion of history. 相似文献
88.
Federico Rossi Maria Liria Turco Liveri 《Colloids and surfaces. A, Physicochemical and engineering aspects》2009,351(1-3):60-64
The kinetics of the oxidation of malonic acid and (its substituted compounds, methyl-, ethyl-, butyl- and benzyl-malonic acid) by ceric ions has been studied at 20.0 °C in the absence and the presence of the surfactant N-tetradecyl-N,N-dimethylamine oxide (C14DMAO). The addition of increasing amounts of C14DMAO influences the rate of the redox process to an extent that significantly depends on the hydrophobicity of the reducing species. The reactivity data together with the estimated binding constants and the standard transfer free energies of the malonic acids from water to the micelles suggest that the malonic acid is confined to the aqueous pseudo-phase while for the other solutes the binding occurs in the palisade layer of micelles. 相似文献
89.
Federico Camia 《Random Structures and Algorithms》2008,33(3):377-408
We consider a type of dependent percolation introduced in 2 , where it is shown that certain “enhancements” of independent (Bernoulli) percolation, called essential, make the percolation critical probability strictly smaller. In this study we first prove that, for two‐dimensional enhancements with a natural monotonicity property, being essential is also a necessary condition to shift the critical point. We then show that (some) critical exponents and the scaling limit of crossing probabilities of a two‐dimensional percolation process are unchanged if the process is subjected to a monotonic enhancement that is not essential. This proves a form of universality for all dependent percolation models obtained via a monotonic enhancement (of Bernoulli percolation) that does not shift the critical point. For the case of site percolation on the triangular lattice, we also prove a stronger form of universality by showing that the full scaling limit 12 , 13 is not affected by any monotonic enhancement that does not shift the critical point. © 2008 Wiley Periodicals, Inc. Random Struct. Alg., 2008 相似文献
90.
In this paper, a simple probabilistic model of coalition formation provides a unified interpretation for several extensions
of the Shapley value. Weighted Shapley values, semivalues, weak (weighted or not) semivalues, and the Shapley value itself
appear as variations of this model. Moreover, some notions that have been introduced in the search of alternatives to Shapley’s
seminal characterization, as ‘balanced contributions’ and the ‘potential’ are reinterpreted from this point of view. Natural
relationships of these conditions with some mentioned families of ‘values’ are shown. These reinterpretations strongly suggest
that these conditions are more naturally interpreted in terms of coalition formation than in terms of the classical notion
of ‘value.’
相似文献