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241.
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243.
A model for non-Arrhenius structural and dielectric relaxation in glass-forming materials is based on defect clustering in supercooled liquids. Relaxation in the cold liquid is highly hindered, and assumed to require the presence of a mobile defect to loosen the structure near it. A mild distribution of free-energy barriers impeding defect hopping can generate a wide distribution of waiting times between relaxation events. When the mean waiting time is longer than the time of an experiment, no characteristic time scale exists. This case directly yields the Kohlrausch-Williams-Watts (KWW) relaxation law. A free-energy mismatch between defect and nondefect regions produces a defect-defect attraction, which can lead to aggregation. This may occur in defect-rich fragile liquids which also exhibit Vogel kinetics. Defect aggregation and correlation in the high-temperature region above the critical consolute temperatureT
c is described using the Ornstein-Zernike theory of critical fluctuations. For a defect correlation length divergence (T-T
c)-/2, a generalized Vogel law for the structural relaxation time results: =0exp[B./(T-T
c)1.5] In the mean-field limit (=1) this provides as good an account of dielectric and structural relaxation in glycerol,n-propanol, andi-butyl bromide as does the original Vogel law, and for the mixed salt KNO3–Ca(NO3)2 and B2O2 it also describes kinetics over their entire temperature ranges. A breakdown of the Vogel law in the immediate vicinity ofT
g is avoided, and the need to invoke extra low-temperature mechanisms to explain an apparent return to Arrhenius behavior is removed.This paper is dedicated to Prof. N. G. van Kampen on the occasion of his 67th birthday. 相似文献
244.
狭义相对论中的与门佯谬 总被引:1,自引:0,他引:1
提出了一个所谓“与门佯谬”问题,并利用狭义相对论进行了详细的分析和计算,消除和此佯谬。 相似文献
245.
246.
V. P. Maslov 《Theoretical and Mathematical Physics》2008,157(2):1577-1594
We obtain a Bose-Einstein-type distribution for the classical vapor. We show that the analogue of the Bose condensate is the
formation of clusters. We write a new PV diagram for interaction with the form of the Lennard-Jones potential using scattering
theory and a strict constraint. We compare our results with experimental data.
Dedicated to the memory of a dear friend, Tolya Karatsuba
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 157, No. 2, pp. 250–272, November, 2008. 相似文献
247.
Space-Time Trigonometry and Formalization of the “Twin Paradox” for Uniform and Accelerated Motions 总被引:1,自引:0,他引:1
Dino Boccaletti Francesco Catoni Vincenzo Catoni 《Advances in Applied Clifford Algebras》2007,17(1):1-22
The formal structure of the early Einstein’s Special Relativity follows the axiomatic deductive method of Euclidean geometry.
In this paper we show the deep-rooted relation between Euclidean and space-time geometries that are both linked to a two-dimensional
number system: the complex and hyperbolic numbers, respectively.
By studying the properties of these numbers together, pseudo-Euclidean trigonometry has been formalized with an axiomatic
deductive method and this allows us to give a complete quantitative formalization of the twin paradox in a familiar “Euclidean”
way for uniform motions as well as for accelerated ones. 相似文献
248.
In this paper, we apply the tunneling of massive particle through the quantum horizon of a Schwarzschild black hole in noncommutative spaeetime. The tunneling effects lead to modified Hawking radiation due to inclusion of back-reaction effects. Our calculations show also that noncommutativity effects cause the further modifications to the thermodynamical relations in black hole. We calculate the emission rate of the massive particles' tunneling from a Schwarzschild black hole which is modified on account of noncommutativity influences. The issues of information loss and possible correlations between emitted particles are discussed. Unfortunately even by considering noneommutativity view point, there is no correlation between different modes of evaporation at least at late-time. Nevertheless, as a result of spacetime noncommutativity, information may be conserved by a stable black hole remnant. 相似文献
249.
According to the Hellinger-Reissner variational principle and introducing proper transformation of variables , the problem on elastic wedge dissimilar materials can be led to Hamiltonian system, so the solution of the problem can be got by employing the separation of variables method and symplectic eigenfunction expansion under symplectic space, which consists of original variables and their dual variables . The eigenvalue - 1 is a special one of all symplectic eigenvalue for Hamiltonian system in polar coordinate . In general, the eigenvalue - 1 is a single eigenvalue, and the classical solution of an elastic wedge dissimilar materials subjected to a unit concentrated couple at the vertex is got directly by solving the eigenfunction vector for eigenvalue - 1. But the eigenvalue - 1 becomes a double eigenvalue when the vertex angles and modulus of the materials satisfy certain definite relationships and the classical solution for the stress distribution becomes infinite at this moment, that is, the para 相似文献
250.
Thaddeus Tarpey 《Journal of multivariate analysis》2000,75(2):3041
Parallel principal axes are introduced and used to investigate the structure of multivariate distributions. In the class of elliptical distributions, it is shown that self-consistency of parallel principal axes characterizes normality. Parallel principal axes are used to illustrate the equivalent event fallacy in the context of self-consistency. Finally, the idea of piecewise principal component axes is introduced and related to an allometric extension model. 相似文献