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91.
T. Aoyama N. Maeda 《The European Physical Journal B - Condensed Matter and Complex Systems》2006,54(2):157-168
The induced Chern-Simons term for a paired electron state is calculated in the
quantum Hall system by using a field theory on the von Neumann lattice.
The coefficient of the Chern-Simons term, which is the Hall conductance,
has not only the usual term proportional to a filling factor due to
P (parity) & T (time reversal) symmetry breaking
but also correction terms due to P & T & U(1) symmetry breaking.
The correction term essentially comes from the Nambu-Goldstone
mode and depends on an infrared limit.
It is shown that the correction term is related to a topological number of a gap function
in the momentum space. 相似文献
92.
93.
Anastasios Mallios 《International Journal of Theoretical Physics》2006,45(8):1552-1588
“Geometry,” in the sense of the classical differential geometry of smooth manifolds (CDG), is put under scrutiny from the point of view of Abstract Differential Geometry (ADG). We explore potential physical implications of viewing things under the light of ADG, especially matters concerning the “gauge theories” of modern physics, when the latter are viewed (as they are actually regarded currently) as “physical theories of a geometrical character.” Thence, “physical geometry,” in connection with physical laws and the associated with them, within the background spacetime manifoldless context of ADG, “differential” equations, are also being discussed. 相似文献
94.
M. Wilkinson B. Mehlig 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,1(4):397-398
We discuss the absorption of electromagnetic radiation in small conducting particles, in the case where the electron motion
is diffusive. We refine an earlier theory in which we calculated the absorption coefficient using an effective potential describing
the screened electric field. Our new theory incorporates the effects of non-locality in the electrical conductivity, and shows
how the two limiting behaviours of the effective potential at high and low frequencies can be derived from a unified theory.
Our results are in full agreement with our earlier calculation.
Received: 3 November 1997 / Accepted: 29 January 1998 相似文献
95.
In this article we investigate charged particles in gauge theories. After reviewing the physical and theoretical problems,
a method to construct charged particles is presented. Explicit solutions are found in the abelian theory and a physical interpretation
is given. These solutions and our interpretation of these variables as the true degrees of freedom for charged particles,
are then tested in the perturbative domain and are demonstrated to yield infra-red finite, on-shell Green’s functions at all
orders of perturbation theory. The extension to collinear divergences is studied and it is shown that this method applies
to the case of massless charged particles. The application of these constructions to the charged sectors of the standard model
is reviewed and we conclude with a discussion of the successes achieved so far in this programme and a list of open questions.
An erratum to this article is available at . 相似文献
96.
T.P. Grozdanov E.A. Solov'ev 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1999,6(1):13-22
The problem of determination of momentum distributions of ejected electrons in slow atomic collisions is studied within the
impact-parameter method by using a dynamic adiabatic basis which takes into account the correct boundary conditions. An expression
is obtained which relates the momentum distribution of the ejected electrons with a coherent sum of the delocalized dynamic
adiabatic eigenstates (elementary wavepackets). The form of the momentum distribution exactly coincides with the form of the total wavepacket in configuration space. General formulas are applied to a model problem of
electron detachment in the process in which the electron-atom interactions are described by the zero-range potentials. In the example considered, the momentum
distribution of ejected electrons, in the center-of-mass frame, exhibits a maximum located in the scattering plane on the
circle of radius (in atomic units), where v is the relative collision velocity and is the impact parameter.
Received: 5 October 1998 相似文献
97.
M D Srinivas 《Pramana》1982,19(2):159-173
This paper is devoted to a study of some of the basic conditions which have to be satisfied by a hidden variable theory in
order that it can reproduce the quantum mechanical probabilities. Of course one such condition, which emerges from the important
theorem of Bell, is that a hidden variable theory has to be non-local. It is shown that a hidden variable theory is also incompatible
with the conventional interpretation of mixed states and the mixing operation in quantum theory. It is therefore concluded
that, apart from being non-local, a hidden variable theory would also necessarily violate the usual assumption of quantum
theory that the density operator provides an adequate characterization of any ensemble of systems, pure or mixed. 相似文献
98.
In this paper certain correspondences have been shown among various formulations of coupled-cluster theories for many electron
closed-shell systems. Specifically it is shown that (i) the energy functional using unitary ansatz of the form exp (T−T
+) is exactly sameorder by order inT with the size-consistent energy functional 〈ψ|H|ψ〉/〈ψ|ψ〉 recently obtained by us in coupled-cluster framework; (ii) in the framework of unitary ansatz of the form exp (T−T
+), both non-variational and variational approaches lead to identical equations upto any given order inT andT
+ inT∼T
2 approximation; (iii) variational procedure using our size-consistent energy functional or using the functional obtained in
the framework of unitary ansatz (as envisaged by Kutzelnigg) leads to energy in both cases, inT∼T
2 approximation, for a total of quadratic powers inT andT
+, same as Cizek’s linearised coupled pair many electron theory energy; (iv) in case of practical calculation of the energy
through the variational procedures using our size-consistent energy functional and the functional in unitary ansatz framework,
there is a loss of upper bound. 相似文献
99.
Summary We discuss some new ideas for improving first-principle muffin-tin orbital-type electronic-structure calculations for complex
crystals such as ternary and multinary compounds. The new ideas include construction of generalized muffin-tin orbitals and
energy-dependent double MTO basis sets, cellular decomposition based on strongly overlapping atomic spheres and evaluation
of matrix elements in the residual interstitial region by extrapolation.
Supported in part by the Office of Naval Research, Contract Number N00014-79-C-0814. 相似文献
100.
George Voutsadakis 《Mathematical Logic Quarterly》2006,52(3):288-294
In this note, it is shown that, given a π ‐institution ? = 〈 Sign , SEN, C 〉, with N a category of natural transformations on SEN, every theory family T of ? includes a unique largest theory system of ?. satisfies the important property that its N ‐Leibniz congruence system always includes that of T . As a consequence, it is shown, on the one hand, that the relation ΩN ( ) = ΩN (T ) characterizes N ‐protoalgebraicity inside the class of N ‐prealgebraic π ‐institutions and, on the other, that all N ‐Leibniz theory families associated with theory families of a protoalgebraic π ‐institution ? are in fact N ‐Leibniz theory systems. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献