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261.
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
262.
O. Sauret D. Feinberg T. Martin 《The European Physical Journal B - Condensed Matter and Complex Systems》2003,32(4):545-548
An electron teleportation protocol, inspired by the scenario by Bennett et al., is proposed in a mesoscopic set-up. A superconducting circuit allows to both inject and measure entangled singlet electron
pairs in an array of three normal quantum dots. The selection of the teleportation process is achieved in the steady state
with the help of two superconducting dots and appropriate gating. Teleportation of the electron spin is detected by measuring
the spin-polarized current through the normal dot array. This current is perfectly correlated to the pair current flowing
inside the superconducting circuit. The classical channel required by Bennett's protocol, which signals the completion of
a teleportation cycle, is identified with the detection of an electron pair charge in the superconducting circuit.
Received 10 December 2002 / Received in final form 14 March 2003 Published online 7 May 2003 相似文献
263.
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
264.
265.
266.
R. Liu M.-L. Liang B. Yuan 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,41(3):571-578
Pairwise thermal entanglement in the three-qubit XXX
Heisenberg model with next nearest neighbor interaction and a nonuniform
magnetic field has been studied. It's found that the next nearest neighbor
interaction has a great effect on the entanglement between the next nearest
neighbor sites, but has slight effect on the nearest neighbor
entanglement (NNE). Applying a magnetic field at the middle site enhances the
next nearest neighbor entanglement (NNNE) sharply when there is a small field
at the side sites and the next nearest neighbor coupling constant is
positive. A staggered magnetic field helps to maintain nearest neighbor
entanglement obviously. 相似文献
267.
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
268.
The massive particles’ Hawking radiation from a spherically symmetric static black hole is investigated with Parikh-Wilczek
method, Hamilton–Jacobi method and Damour–Ruffini’s method. When energy conservation is considered, the same result can be
concluded that the radiation spectrum is not precisely thermal. The corrected spectrum is consistent to the underlying unitary
quantum theory, which can be used to explain the information loss paradox possibly.
相似文献
269.
X. Wang K. Mølmer 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,18(3):385-391
For pairs of particles extracted from a symmetric state of N two-level systems, the two-particle density matrix is expressed in terms of expectation values of collective spin operators
for the large system. Results are presented for experimentally relevant examples of pure states: Dicke states | S, M>, spin coherent, and spin squeezed states, where only the symmetric subspace, S = N/2 is populated, and for thermally entangled mixed states populating also lower S values. The entanglement of the extracted pair is then quantified by a calculation of the concurrence, which provides directly
the entanglement of formation of the pair.
Received 9 May 2001 and Received in final form 16 November 2001 相似文献
270.
Simpson’s paradox reminds people that the statistical inference in a low-dimensional space probably distorts the reality in a high one seriously.To study the paradox with respect to Yule’s measure, this paper discusses simple collapsibility, strong collapsibility and consecutive collapsibility, and presents necessary and sufficient conditions of them.In fact, these conditions are of great importance for observational and experimental designs, eliminating confounding bias, categorizing discrete variables and so on. 相似文献